Process for breaking petroleum emulsions



Patented Jan. 17, 1928.

UNITED STATES PATENT OFFICE.

MELVIN DE GROOIE, OF ST. LOUIS, AND WILBUR C. ADAMS, 01F UNIVERSITY CITY, MISSOURI, ASSIGNORS TO WM. S. BARNICKEL & COMPANY, OF WEBSTER GROVES, MISSOURI, A. CORPORATION OF MISSOURI.

PROCESS FOR BREAKING PETROLEUM EMULSIONS.

No Drawing.

This invention relates to the treatment of emulsions of mineral oil and water, such as petroleum emulsions, for the purpose of separating the oil from the water.

5 Petroleum emulsions are of the water-1noil type and comprise fine droplets of natural occurring waters or brines dispersed in a more or less permanent state throughout the oil which constitutes the continuous phase 1 of the emulsion. They are obtained from producing wells and from the bottoms of 01] storage tanks and are commonly referred to as cut oil, roily oil, emulsified oil and bottom settlings i The object of our invention is to prov de a novel process for breaking or separating such petroleum emulsions, which is distinguished from prior chemical processes heretofore used for breaking such emulsions, in that it contemplates subjecting the emulsion to the action of a treating agent formed from tar acid oil, a sulphonic body and a soapforming body, combined in such a way that only the hydrox aromatics of the tar acid oil are chemical y combined with the sulhonic body and with the soap-formmg body, the remaining non-hydroxy' hydrocarbons of the tar acid oil acting simply, as a diluent.

One method that can be employed to produce the treating agent used in our process consists in taking tar acid oil of a certain approximate hydroxy aromatic content and adding suflicient sulphuric acid to the same to sulphonate substantially all of the hydroxy aromatics, but practically none of the non-hydroxy aromatics, it being preferable to use commercial tar 'acid oil whose hydroxy aromatic content varies from 22 fi 40 to 32 and sulphonate the same with sulphuric acid of approximately 66 B. strength. The above action or treatment produces a sulphonate which thereafter is mixed with a soap-forming body, preferably a fatty body, in the approximate proportions of one volume of the sulphonate to two volumes of the soap-forming body. Subsequently, this mixture is subjected to the action of a relatively small amount of sulphuric acid, usually about 20% by. volume of the mixed acids, thereby causing a reagent of the so-called Twitchell type to be formed from only the hydroxy aromatics, the re- Application filed August 11, 1926. Serial No. 128,705.

mainin non-hydroxy aromatics beingunaffected by the above treatment and simply acting as a diluent. As is well understood in'this art, the term Twitchell reagents is generally used to designate sulpho-aromatic, soap-formim acids containing one soapforming car hoxyl group for each aromatic radical, and it is in this sense that We have herein used the term Twitchell reagents. After the'sulphuric acid has been added to the mixed sulphonate and soap-forming body in approximately the proportions specified, i. e., 20% by volume, the mass is allowed to stand for approximately 24 hours and thereafter it is thoroughly washed and separated.

Generally, tar acid oil will carry about 25% of hydroxy bodies so that the above described proportions of two volumes of the soap-forming body to one volume of the sulphonate is approximately correct in most instances, but whenever the percentage of the hydroxy bodies in the tar acid oil is greator or less, the percentage of the fatty material that' is added to the same will have to be varied so as to maintain the approximate ratio specified.

We prefer to use a modified oleic acid to form the fatty body or soap-forming body of the treating agent used in our process, as we have found that such acid combines readily with the tar acid oil sulphonate, the modi fied,oleic acid being obtained by treating oleic acid with sulphuric acid, varying from 10% to 50% by Weight, and subsequently, washing the same to remove the sulphuric acid. We wish it to be understood, however, that various materials can be used to furnish the soap-forming body of the compound used in our process, such, for example, as rosin, resinic substances and mineral oil substances, such as naphthenic acids. The essential thing is to use a material of the or anic group that is capable of combining wit an alkali to form a soap, such substances having the ability to form detergents, even after modification, by means of chemical reaction, provided the modified substance bears a simple genetic relationship to the parent material from which it was derived. Accordingly, we have herein used the term de; tergent-forming material to designate one ingredient of the treating agent contemsions.

plated by our process and to mean both the modified and unmodified fatty bodies, resins and naphthenic bodies. We have also used the term sulpho-aromatic detergentforming acid to mean a body of acidic character having an aromatic radical and sulphonic radical, and a detergent-forming radical of the kind previously referred to.

The above procedure produces a compound or product containing an hydroxy moncyclic sulplio-aromatic detergent-forming group, an uncombined detergentforming group, and non-hydroxy tar acid oil hydrocarbons. Usually, upon analysis said. compound will be found to be composed of about 32% of a reagent of the Twitchell type, 32% of an oelic acid fatty body, made up of modified and unmodified oleic acid, and about 22% of non-hydroxy non-sulphonated aromatics, the remainder of the compound consisting of water, sulphuric acid and other impurities,

or the combining base, after. combination with an alkali.

In producing the compound that is used as the treating agent in our process, the acidic material can be converted into an ester, such as ethyl ester; it can be converted into Water-insoluble salts, such as calcium or magnesium salts, or it can be converted into water-soluble salts, such as an alkali salt or ammonium salt. Said materials can be used alone or in combination with other suitable chemical treating agents, and they can be used in diluted form or in undiluted form.

' When used in diluted form water or oil is the most desirable solvent to use.

In practisingour process, the treating agent or compound above described is brought into contact with an emulsion either by introducing the treating agent into a well in which the petroleum emulsion is being produced; introducing the treat-ing agent into a conduit through which a petroleum emulsion is flowing; introducing the treating agent into a tank in which a petroleum emulsion is stored, or introducing the treating agent into a container that holds sludge obtained from the bottom of an oil storage tank. The treating agent can even be introduced into a producing well in such a way that it can become mixed with water or oil that is emerging from the ground before said water and. oil enter the barrel of. the well pump or the tubing up through Which said water and oil flow to the surface of the ground. After any of the various treatments above referred to the emulsion is allowed to stand in a quiescent state'at a suitable temto separate from the oil, or it may be passed through a variet of apparatus, such as hay tanks, gun barre s, etc, such as are now commonly used for breaking petro eum emul- It may even be passed through a heating apparatus, a centrifugal or an electrical dehydrator, or an emulsifying device, with or without the addition of water to the emulsion, or it may be subjected to action by a combination of two or more of the devices above referred to. i

Having thus described our invention, What we claim as new and desire to secure by Letters Patent is: Y

1. A process for breaking or separating petroleum emulsions, characterized by subjecting the emulsion to the action of a treating agent comprising approximately 30% of an hydroxy monocyclic detergent-forming group, 30% ofa detergent-forming group uncombined with aromatics, and20% of non-hydroxy tar acid oil aromatics.

2. A process for breaking or separating petroleum emulsions, characterized by subjecting the emulsion to the action of a treating agent consisting of a salt comprising approximately 30% of an hydroxy monocyclic sulphoaromatic detergent-forming group, 30% of a detergent-forming group uncombined with aromatics, and 20% of nonhydroxy tar acid oil, aromatics.

3. A process for breaking or separating petroleum emulsions, characterized by subjecting the emulsion to the action of a treating agent consisting of a water-soluble salt comprising approximately 30% of an hydroxy monocyclie sulphoaromatic detergentforming group, 30% of a detergent-forming group uncombined with aromatics, and 20% of non-hydroxy tar acid oil aromatics.

4. A process for breaking or separating petroleum emulsions, characterized by subjecting the emulsion to the action of a treating agent consisting of an ammonium salt comprising approximately 30% of an liydroxy monocyclic sulphoaromatic detergentforming group, 30% of a detergent-forming group uncombined with aromatics and 20% of non-hydroxy tar acid oil aromatics.

5. A process for breaking or separating petroleum emulsions, characterized by subjecting the emulsion to the action of a treating agent comprising approximately 30% of an hydroxy monocyclic sulphoaromatic fatty group, 30% of a detergent-forming sulphoaromatic v group uncombined with aromatics, and 20% proximately 30% of an hydroxy monocyclic sulphoaromatic fatty group, 30% of a detergent-forming group uncombined with aromatics, and 20% of non-hydroxy-tar acid =oil aromatics.

7. A process for breaking or separating petroleum emulsions, characterized vby subjecting the emulsion to the action of a treating agent consisting of a water-soluble salt comprising approximately 30% of an hydroxy monocyclic sulphoaromatic fatty group, 30% of adetergent-forming group d uncombined with aromatics, and 20% of non-hydroxy tar acid oil aromatics.

' 8. A. process for breaking or separating etroleum emulsions, characterized by subecting the emulsion to the action of a treating agent consistin 

